Blowing-engine.



Patented Nov. |8,' |902.

c. Rnmson. BLOWING ENGINE.

` (Application led Oct. 19, 1899.)

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Patented Nov. ls, |902. C. ROBINSON.

BLOWING ENGINE. (Application med oct. 19, Issa.)

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(No Modal.)

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l No. 7|3,687. Patented Nov. I8` |902. C. RUBINSON.

BLOWING ENGINE.

(Application filed Oct. 1.9, 1898.)

3 Sheesf-Sheet 3.

(No Model.)

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OYRUS ROBINSON, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THE uVVESTINGHOUSE MACHINE COMPANY, OF PITTSBURG, PENNSYLVA- NIA, ACORPORATION OF PENNSYLVANIA.

BLOWlNG-ENGINE.

SPECIFICATION forming part of Letters Patent No. 713,687, dated November18, 1902.

Application filed October 19, 1899` Serial No. 734,114. (No model.)

To f1/ZZ whom, t may concern;

Beit known that I, OYRUS ROBINSON, a subject of the Queen of GreatBritain, residing at Pittsburg, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inBlowing- Engines, of which the following is a specilication, referencebeing had therein to the accompanying drawings.

My present invention has for its principal objects to improve theconstruction and operation of the outlet-valves of blowing-engines andto render more accurate and effective the means for operating theinlet-valve within the hollow reciprocating piston-rod.

In order to make the invention more clearly understood, I have shown inthe accompanying drawings means for carrying the same into practicaleffect without limiting my improvements in their useful applications tothe particular constructions which for the sake of illustration I havedelineated.

In said drawings, Figure lis a central section of a mechanism embodyingmy invention, the parts shown including the cylinder and piston-valveand piston-rod and the inlet and discharge valve mechanism. Fig. 2 is anend view of the parts in Fig. l. Fig. 3 is a section, on a larger scale,of one of the discharge-valves. Fig. 4 is a cross-section on the line o;c of Fig. l. Fig. is a side view of one of the movable parts of theguide that controls the piston-valve. Fig. 6 is a sectional view showingthe guide and the parts fitted therein which control the positions ofthe piston. Fig. 7 is a View of the parts in Fig. 6, shown at rightangles thereto. Fig. S is a view, partly in side elevation and partly insection, illustrating a modication of the valve-guiding mechanism. Fig.9 shows the parts in Fig. 8 when looked at from another direction. Fig.l0 is a perspective view of the cam detached. Fig. 1l is a crosssectiouon the line 'y 'y of Fig. 6.

VIn the drawings, A indicates the cylinder, which may be of any usual orpreferred sort as concerns its details. Nithin the cylinder there is apiston B, which also may be constructed in any preferred way, although Ipre- Jfer to have it substantially as shown--that is to say, to have itformed in two parts b and U, which constitute halves separable aboutcentrally on a plane transverse to the axis of the cylinder, shaped tohave annular grooves or recesses b2 at their centers, which when the twoparts b b are put together provide a groove or annular recess, in whichcan be fitted a flange f5 on the piston-rod. At the periphery the pistoncan, if required, be provided with a packing of any suitable sort. Thetwo halves are joined together by bolts b3. The upper or lower heads ofthe cylinder are respectively indicated by O and E. These also in manyrespects may be similar to those that are well known or can beconstructed in any preferred way so long as they are adapt-V ed to meetthe requirements of my construction. As shown, each has a wall c at theend ofthe cylinder-chamber,perforated to receive the valve-seats c', andan outer Wall c2, there being preferably between the walls c and c2 aspace or chamber c3.

F indicates the part which serves the purpose of a piston-rod and alsoof a valvechamber. It is hollow and fitted to the heads O and E, thelatter having central apertures at c, provided with packings or glands,if required. At f5 this hollow piston-rod has an outwardly-extendingannular ange fitted in the aforesaid groove or recess b2 in the twopartpiston. At points immediately adjacent to the piston, both above andbelow it, there are ports, as at f2f3, of any suitable number,preferably a relatively large number, preferably formed as inclinedslots through the hollow rod.

I will herein refer more particularly to a compressor orcompressorengine, and the parts already referred to may be considered asconstituting parts of such a mechanism. /Vhen the piston and cylinderabove set forth are to be used for compressing air, for instance, thepiston can be connected to the piston-rod of an engine by a suitableconnec tion, such as shown at I'.

Vithin the hollow piston-rod F there is fitted the valve Gr, which isalso tubular and of a suitable length, such as that shown. This can havea motion longitudinally of and independently of the piston-rod. Withthese IOL) parts are combined others, such that when the piston B andthe hollow rod F are moving in either direction the ports f2 or ,f3 infront of the piston are closed and those in the rear thereof are opened.Such closing and opening of the ports is effected by the proper movementof the valve G. The movements of the valve are accomplished as follows:

H is a'rod pivotally connected at g2 to the valve G. At its upper endthe rod is connected to a lever I, which in turn is connected to a leverJ, pivoted by means of a shaft L, mounted in bearing-ears M M, securedto the upper end of the hollow piston-rod F. The lever I extends topoints beyond the axis at L and is Weighted, preferably by having castintegral with it a weight K, which serves to counterbalance the lever I,the rod H, and the valve G. If preferred, the lugs or ears M M can beformed integral with a sleeve or collar N, which can be secured to thehollow piston-rod.

The lever J carries a laterally-projecting crank or pin at Q, preferablyprovided with an antifriction-roller. This is fitted and travels in away or groove P in the cam O, this cam and its groove being such as toimpart to the leversJand I and the valve G, connected thereto,themovements that are required for the latter. As the piston descends inthe direction of the arrows in Fig. l the roller Q approaches the part pof the cam -groove and travels through this partuntilitimpingeson thestoppin U. The latter is formed with a head U2 having a beveled orinclined edge u, and with a stem or shank Us. It is arranged in suchmanner that it can move longitudinally transverse tothe cam-groove. Thehead part u2 is somewhat larger than the shank or stem U3, and a springu is placed around the latter, said spring bearing in one directionagainst the head U2 and in the other direction against a stop-nut u2,through which the stem or shank can fit. When the roller Q strikes thebeveled face u, as aforesaid, it forces the stop U outward against thetension of the springtt. When the roller reaches the end of thecam-groove P, the stop U is forced inward immediately behind the rollerand the latter is prevented from returning along that part of thecam-groove through which it has just moved and is compelled to movealong the opposite part. For instance, when the roller reaches thebottom of the cam-groove (moving in the direction of the arrows shown inFig. l) the stop U after the roller has passed it prevents the latterfrom moving backward through the same partof the groove and compels itto move upward through the opposite part. In doing so the roller takes apathway differently related to the axis of the shaft L, and consequentlythe lever I is thrownv in the opposite direction from that illustratedin Fig. l, and as a result the rod H and the valve G are caused tooccupy different positions as to the ports f2 and f3. When the roller Qreaches the upper part of its path, it impinges upon the upper stop U,constructed and arranged similarly to that above described, and afterpassing it is compelled to follow the right-hand part of its path whendescending.

It will be seen that when the piston is descending the valve G is insuch position that the ports f2 above the piston are opened, while thosebelow it are closed, and vice versa, and consequently the lower part ofthe cylinder below the piston is a closed chamber, wherein the air iscompressed and driven past the valve D', the ports above the pistonbeing at the same time opened, so that air can enter the upper part ofthe cylinder; but assoon as the stroke of the driving-engine is reversedthe position of the valve G is also reversed through the action of theroller Q and its cam-guideway-that is to say, the upper part of thecylinder becomes a closed chamber when the piston is moving outward,while the lower part is opened for the reception of air.

The valves by means of which the passage of the air from the cylinder iscontrolled are herein shown as being constructed as follows: a is a cupformed preferably of steel and iitted to and guided on a tubular guideb. The latter is hollow and formed with a boss or thickened portion atthe inner end, which is perforated and provided with a metallic packingo. Through the latter passes a tubular rod or guide-bar d, which isarranged to bear against the inner face of the end of the valve proper,a. This guide d is at its outer end fitted into a guide-plug g, andaround it there is placed a coiled spring f, which at its outer endbears against the plugg and at its inner end bears against a flange orstop-collar e, rigidly secured to the guide d. The plug g is of thenature of a'hollow nut, which can be adjusted in or out to regulate thetension of the spring f.

When the pressure of the air within the cylinder A exceeds the pressurein the receiver, (with which communicate the chambers c3 and the ductsD2 and D3,) the valve Otis forced from its seat and the air dischargedfrom the cylinder, and as the valve moves outward it presses the guide dalso outward against the tension of spring f, and when the pressurefalls again said* spring, bearing against the collar e, again compelsthe guide d to force the valve ot tightly against its seat.

Apertures k 7c are formed in the valve aat a suitable distance from thelower end of the latter, which apertures can be moved out to pointsbeyond the ends of the tubular guide b, and as soon as they do passbeyond said end IOO IIC

the escape of air from the interior of the valve is shut off; but aquantity thereof rel mains, which serves as a cushion for the valve andprevents the latter from striking against the end of the guide h.

It is sometimes necessary to throw a valve out of operation while thecompressor is at work, and heretofore it has been necessary to shut downthe whole compressor in order to accomplish this whenever it is desiredto renew the springj1 or to make other similar changes. Ihave obviatedthis stoppage of the mechanism as follows: I employ a stop Z, which canengage with the valve or with some ofthe parts connected thereto andprevent the valve being opened, although allowing` the rest of themechanism to continue in operation. The stop Z, as shown, consists of anadjustable arm held by a pivot at t", it being adapted to be turned intosuch position as to engage with the abutment-collar e on the guide rodor tube d. In Fig. 3 this adjustable stop is shown in full linesinitsiuactive position, while in dotted lines it is shown as engaging withand lyingr immediately outside of the stop-collar e. When it is in thelatter position, it will be seen that the guide rod or tube d cannotmove outward and that therefore the valve is held against opening. Vhenthe stops are in such position, the plug-nut gcan be withdrawn entirelyor as far as desired, and, if required, the spring f can be withdrawnand another put in place thereof, and while these steps are being takenthe engine and compressor can continue in operation, for, as will beseen upon examining Fig. 2, there are several such valves at each end ofthe cylinder.

With respect to the inlet-valve G the following characteristic matterswill be noted: First, I provide a valve which is perfectly balanced andso disposed as to require only such an amount of power as will overcomefriction and inertia; second, I provide one which requires only aminimum clearanceto wit, a clearance of not more than one-half of oneper cent. in cylinders of seven feet in diameter; third, I do away withthe necessity of two piston-rods, which are commonly used with manytypes of valves in such mechanisms, and I centralize the strainsdirectly with relation to the rod of the steam-engine piston, myconstruction as a result being much lighter and safer, and, stillfurther, I obviate the necessity of ecoentrics or similar devices fortransmitting motion from the engine-shaft to the valve, such as aregenerally used for actuating positively-actuated inletvalves.

Various means may be employed to actuate or shift the valve G. In placeof the mechanism for this purpose shown in Fig. l I may employ thatillustrated in Figs. S and 9, in which the valve-actuating lever I andshaft Il are connected by an arm l with a wheel or crank 2. Said arm iskeyed on the shaft L, so as to be capable of oscillating it, and isjointed at its other end with the wheel 2 by a wrist-pin 3. The wheel ismounted so as to rotate on a shaft or stud 4, fixed or mounted on thebody of the engine-cylinder or cylinder-head, and when it is necessaryit is driven or is given a tendency to turn in the proper direction by awire rope 5 or other Suitable device from the engine-shaft. The

wheel 2 is so designed and arranged as to make one revolution for eachcomplete throw of the piston-rod H, and preferably the radius of the pin8 from the center shaft et is equal to that of the engine-crank. Theactuation of the arm 1 by the pistou-rod F will turn the wheel or crank2; but the action of the connection 5 insures that the wheel shall turnpast the lines on which the arm 1 will not'be effective and shallcontinuously rotate in the same direction. It will be understood fromthe above description that as the piston-rod F reciprocates the parts I,L, and 1 travel with it, but the simultaneous rotation of the wheel 2controls the position of the arm l and of the valve G, causing thelatter to open the upper ports]c2 and close the lower ports f3 as thepiston moves downward and v ice versa as it moves upward.

l. In an air-compressor, the combination of a stationary cylinder,outlet-valves for oontrolling the escape of compressed air and adaptedto yield to the air, springs for holding said valves closed against thepressure of the air, a piston adapted to reciprocate in said stationarycylinder, a piston-rod connected to said piston, power mechanismconnected to the said piston-rod to drive it, said rod being providedwith an air-duct, a valve in said air-duct, a lever for moving the saidvalve carried by and movable with the piston-rod, and means for movingsaid lever independently of the movement of the pistonrod, substantiallyas set forth.

2. In a blowing engine or compressor, the combination of a stationarycylinder, a reciprocatin g piston therein, valve-seats in thecylinder-wall, one or more on each side of the piston, spring-heldvalves in said seats, a piston-rod having an air-duct and having portsabove and below the reciprocating piston, a driving-engine connected tothe said pistonrod, a valve in the air-duct in the piston-rod, a leverconnected to the valve, and pivotally connected to the piston-rod, andstationary devices for moving the lever around its fulcrum and movingthe valve opposite to the movement of the piston, substantially as setforth.

3. In an air-compressor, the combination of the stationary cylinder, thespring-held outlet-valves in the wall of the cylinder, the reciprocatingpiston in the cylinder, the pistonrod connected to the piston andprovided with an air-duct, and having ports above the piston and portsbelow it, a hollow balanced valve alternately closing and opening theupper and lower ports, a lever connected to the said valve and movingbodily with the piston, and devices held against longitudinal movementand engaging with the lever and causing the valve to reciprocatelongitudinally of the piston-rod, substantially as set forth.

4. The combination of the stationary cylinder, the piston reciprocatingin the cylinder, the piston-rod having an air-duct, and ports XOO IIO

above the cylinder and ports below it, a valve in the said air-duet forcontrolling said ports, an engine connected to the piston for driving itfor compressing the air, a lever conneeted to the valve, and astationary guide for the lever havinga substantially rectilinearguide-Way, and two curved guideways at the ends of the rectilinear guideway,substantially as set forth.

ing a valve-port and valve-seat, of the valve mechanism yeomprisingahollow-cup movable toward and from the valve-seat, a spring for holdingthe valve against the seat, and a positive lock for looking the valveagainst the seat, substantially as set forth.

7. The combination, with the cylinder, having a valve-port and avalve-seat, of the Valve adapted to rest upon said seat, a springarranged to normally tend to hold the valve against the seat, aremovable holder for the spring, and means for positively looking,l thevalve against the seat, when the springis removed, substantially as setforth.

In testimony whereof I affix my signature in presence of two witnesses.

CYRUS ROBINSON.

Witnesses:

H. H. HORNE, E. E. ARNOLD.

